The epidemiology of biopsy-positive giant cell arteritis: special reference to cyclic fluctuations

The impact of month and season on the incidence of giant cell arteritis: an Intelligent Research in Sight (IRIS) Registry analysis

PURPOSE

Previous investigations into the relationship between season and the incidence of giant cell arteritis (GCA) have produced conflicting results. This study aimed to explore the impact of season and new diagnoses of GCA in a more definitive sense by employing the large dataset of the Intelligent Research in Sight (IRIS) database.

METHODS

The IRIS Registry was queried to identify new cases of GCA from 2013 to 2021. Statistical analyses were performed to determine the significance of the relationship between the time of year and the incidence of GCA on regional and nationwide bases via Cochran's Q statistical test.

RESULTS

A total of 27,339 eyes with a new diagnosis of GCA were identified. Neither the month nor the season of the year correlated with the incidence of GCA, regardless of geographic location within the USA (p > 0.05 for each variable).

CONCLUSIONS

In the USA, the incidence of GCA does not appear to vary by month or season. While this finding contradicts certain previous studies that identified a relationship, the cohort of patients identified from the IRIS Registry is much larger than that of previous investigations. Clinicians should be mindful of the possibility of GCA, regardless of the time of the year.

Environmental Triggers for Vasculitis

Systemic vasculitides are autoimmune diseases characterized by vascular inflammation. Most types of vasculitis are thought to result from antigen exposure in genetically susceptible individuals, suggesting a likely role for environmental triggers in these conditions. Seasonal and geographic variations in incidence provide insight into the potential role of environmental exposures in these diseases. Many data support infectious triggers in some vasculitides, whereas other studies have identified noninfectious triggers, such as airborne pollutants, silica, smoking, and heavy metals. We review the known and suspected environmental triggers in giant cell arteritis, Takayasu arteritis, polyarteritis nodosa, Kawasaki disease, and antineutrophil cytoplasmic antibody-associated vasculitis.

Global epidemiology of vasculitis

The many forms of vasculitis are characterized by inflammation of blood vessels, leading to potentially long-term sequelae including vision loss, aneurysm formation and kidney failure. Accurate estimation of the incidence and prevalence has been hampered by the absence of reliable diagnostic criteria and the rarity of these conditions; however, much progress has been made over the past two decades, although data are still lacking from many parts of the world including the Indian subcontinent, China, Africa and South America. Giant cell arteritis occurs in those aged 50 years and over and seems to mainly affect persons of northern European ancestry, whereas Takayasu arteritis occurs mainly in those aged under 40 years. By contrast, Kawasaki disease mainly occurs in children aged under 5 years and is most common in children of Asian ancestry, and IgA vasculitis occurs in children and adolescents. Although much less common than giant cell arteritis, the different forms of antineutrophil cytoplasmic antibody-associated vasculitis are being increasingly recognized in most populations and occur more frequently with increasing age. Behçet syndrome occurs most commonly along the ancient silk road between Europe and China. Much work needs to be done to better understand the influence of ethnicity, geographical location, environment and social factors on the development of vasculitis.

Cardiovascular drug treatment, statins and biopsy-confirmed giant cell arteritis: a population-based case-control study

Objective

To determine whether exposure to cardiovascular medications and statins is associated with increased risk of giant cell arteritis (GCA).

Design

The population-based case–control study comprised a cohort of patients with biopsy-confirmed GCA linked to the Swedish Prescribed Drug Register to identify all exposure to drugs prior to diagnosis of GCA. Ten controls per GCA case, matched for age, sex and residential area, were included. Using corresponding Anatomical Therapeutic Chemical codes, ACE inhibitors, angiotensin II receptor blockers, beta-blocking agents, calcium antagonists, diuretics, statins and cardiac therapy drugs were investigated from July 1, 2005 to the diagnosis/index date. A conditional logistic regression model was fitted adjusted for income, education level and marital status. We repeated the analyses including only new drug users excluding those with any prescription during the year from July 1, 2005 to July 1, 2006.

Results

574 cases (29% men) of diagnosed GCA and 5740 controls (29% men) were included. The mean age at diagnosis is 75 years (SD 8). Of the GCA cases, 71% had at least one dispensation of a cardiovascular drug prior to the index date, compared to 74% of controls. The ORs for the association of target drug exposure with GCA were <1 for most drugs, but close to 1 in the analysis of new users. Statins were consistently associated with lower risk of GCA, OR 0.74 (95% CI 0.61 to 0.90).

Conclusion

Statins may be associated with lower risk of incident biopsy-confirmed GCA. No association was evident for other studied drugs.

Seasonal variation in biopsy-proven giant cell arteritis in Eastern Denmark from 1990-2018

PURPOSE

The purpose of this study was to investigate seasonal variation in cases of biopsy-proven GCA in eastern Denmark in a 29-year period.

METHODS

Pathology records of all temporal artery biopsies in eastern Denmark between 1990 and 2018 were reviewed. For each patient, data were collected which included age, sex, date of birth and biopsy result. Seasonality was evaluated using logistic regression and Poisson regression analysis. Lastly, an explorative pilot study was conducted to investigate a possible association between three weather parameters (average temperature, amount of rain and hours of sunshine) and the biopsy outcome.

RESULTS

One thousand three hundred twenty-three biopsies were included of which 336 fulfilled objective criteria for GCA diagnosis. Mean age at diagnosis was 75.6 years (range 52-94 years). Among the biopsy-proven cases of GCA, there were 223 women (66.3%, mean age 76.2 years) and 113 men (33.7%, mean age 74.4 years) giving a female to male ratio of 1.97:1. The peak occurrence of GCA was in the 70-79 years age group. Statistical analysis of seasonal variation showed an increased risk of a positive biopsy during summer compared to autumn (p = 0.037). No association between the three weather parameters and the biopsy outcome was found.

CONCLUSION

In this study of biopsy-proven GCA in a large Danish patient cohort, the occurrence of GCA showed seasonal variation with higher occurrence in the summer months when compared to autumn. Future studies pooling all cases of GCA worldwide are needed to determine seasonality in the occurrence of GCA.

Epidemiology of biopsy-confirmed giant cell arteritis in southern Sweden - an update on incidence and first prevalence estimate

Objective

To characterize the epidemiology of temporal artery biopsy-positive (TAB+) GCA, including trends in incidence, seasonal variation and prevalence in Skåne, the southernmost region of Sweden.

Methods

All histopathology reports of TABs from 1997 through 2019 were reviewed to identify patients diagnosed with TAB+ GCA. Incidence rates based on the 23-year period and the point-prevalence at 31 December 2014 were determined. An alternative prevalence calculation included only TAB+ GCA patients living in the study area and receiving immunosuppressant therapy on the point-prevalence date.

Results

One thousand three hundred and sixty patients were diagnosed with TAB+ GCA (71% female). The average annual incidence 1997–2019 was 13.3 (95% CI: 12.6, 14.0) per 100 000 inhabitants aged ≥50 years and was higher in females (17.8; 95% CI: 16.7, 18.9) than in males (8.2; 95% CI: 7.4, 9.0). The age- and sex-standardized incidence declined from 17.3 in 1997 to 8.7 in 2019, with incidence ratio (IR) of 0.98 per year (95% CI: 0.98, 0.99). A seasonal variation was observed with higher incidence during spring than winter [IR = 1.19 (95% CI: 1.03, 1.39)]. The overall point-prevalence of TAB+ GCA was 127.1/100 000 (95% CI: 117, 137.3) and was 75.5 (95% CI: 67.7, 83.3) when including only patients receiving immunosuppressants.

Conclusion

Over the past 2 decades, the incidence of biopsy-confirmed GCA has decreased by ∼2% per year. Still, a high prevalence of GCA on current treatment was observed. More cases are diagnosed during spring and summer than in the winter.

A meta-analysis of the epidemiology of giant cell arteritis across time and space

INTRODUCTION

Giant cell arteritis (GCA) is a common large vessel vasculitis in those over age 50 years. This meta-analysis examined the geographical and temporal distribution of the incidence, prevalence, and mortality of GCA.

METHODS

A systematic review was conducted using EMBASE, Scopus, and PubMed from their inceptions until 2019. Studies were included if they reported at least 50 or more GCA patients and defined the location and time frame. Articles on mortality were included and standardized mortality ratio (SMR) was extracted where possible. Mean pooled prevalence, incidence, and SMR were calculated using a random effects model. Linear regression was used to explore correlations between latitude and incidence, prevalence, and mortality.

RESULTS

Of the 3569 citations identified, 107 were included. The pooled incidence of GCA was 10.00 [9.22, 10.78] cases per 100,000 people over 50 years old. This incidence was highest in Scandinavia 21.57 [18.90, 24.23], followed by North and South America 10.89 [8.78, 13.00], Europe 7.26 [6.05, 8.47], and Oceania 7.85 [- 1.48, 17.19]. Pooled prevalence was 51.74 [42.04, 61.43] cases per 100,000 people over age 50. Annual mortality was 20.44 [17.84, 23.03] deaths/1000. Mortality generally decreased over the years of publication (p = 0.0008). Latitude correlated significantly with incidence (p = 0.0011), but not with prevalence, or mortality.

CONCLUSIONS

GCA incidence varies nearly 3-fold between regions and is highest in Scandinavia but not significantly. Mortality may be improving over time.

Trajectory of Healthcare Resource Utilization in Giant Cell Arteritis: A Population-based Study

OBJECTIVE

To estimate the healthcare resource utilization (HRU) in patients with giant cell arteritis (GCA) compared with the general population in southern Sweden.

METHODS

The study sample comprised 653 patients with GCA along with 10 age-, sex-, and residency area-matched reference subjects per patient. Data on public and private healthcare consultations and hospitalizations were extracted from the Skåne Healthcare Register. We assessed trajectories of primary and specialist healthcare visits, as well as hospital admissions and inpatient days from 3 years before through 5 years after the date of GCA diagnosis for patients and matched references. HRU was analyzed using generalized estimating equations adjusted for sex, age at the index year, calendar year of diagnosis, education, income, marital status, place of birth, and Charlson Comorbidity Index. Inverse probability weighting was used to account for dropout during study.

RESULTS

Patients with GCA had higher rates of healthcare visits than the references from the year before GCA diagnosis and up to 4 years after diagnosis, with the largest relative (rate ratio 1.85, 95% CI 1.68-2.05) and absolute (mean difference 10.2, 95% CI 8.1-12.3 visits per person) differences in the year of diagnosis. Similar trajectories were observed for primary and specialist healthcare visits. For hospital admissions and inpatient days, the differences disappeared 1 year after diagnosis date.

CONCLUSION

Patients with GCA utilized healthcare services at a significantly higher rate than the reference population. The increased utilization among Swedish patients with GCA was evident 1 year before and prolonged up to 4 years after diagnosis date.

Aortitis: recent advances, current concepts and future possibilities

Broadly defined, aortitis refers to inflammation of the aorta and incorporates both infectious and non-infectious aetiologies. As advanced imaging modalities are increasingly incorporated into clinical practice, the phenotypic spectrum associated with aortitis has widened. The primary large vessel vasculitides, giant cell arteritis and Takayasu arteritis, are the most common causes of non-infectious aortitis. Aortitis without systemic disease or involvement of other vascular territories is classified as clinically isolated aortitis. Periaortitis, where inflammation spreads beyond the aortic wall, is an important disease subset with a distinct group of aetiologies. Infectious aortitis can involve bacterial, viral or fungal pathogens and, while uncommon, can be devastating. Importantly, optimal management strategies and patient outcomes differ between aortitis subgroups highlighting the need for a thorough diagnostic workup. Monitoring disease activity over time is also challenging as normal inflammatory markers do not exclude significant vascular inflammation, particularly after starting treatment. Additional areas of unmet clinical need include clear disease classifications and improved short-term and long-term management strategies. Some of these calls are now being answered, particularly with regard to large vessel vasculitis where our understanding has advanced significantly in recent years. Work extrapolated from temporal artery histology has paved the way for targeted biological agents and, although glucocorticoids remain central to the management of non-infectious aortitis, these may allow reduced glucocorticoid reliance. Future work should seek to clarify disease definitions, improve diagnostic pathways and ultimately allow a more stratified approach to patient management.

Negative associations for fasting blood glucose, cholesterol and triglyceride levels with the development of giant cell arteritis

Objectives

To investigate metabolic features that may predispose to GCA in a nested case–control study.

Methods

Individuals who developed GCA after inclusion in a population-based health survey (the Malmö Preventive Medicine Project; N = 33 346) were identified and validated through a structured review of medical records. Four controls for every validated case were selected from the database.

Results

A total of 76 cases with a confirmed incident diagnosis of GCA (61% female, 65% biopsy positive, mean age at diagnosis 70 years) were identified. The median time from screening to diagnosis was 20.7 years (range 3.0–32.1). Cases had significantly lower fasting blood glucose (FBG) at baseline screening compared with controls [mean 4.7 vs 5.1 mmol/l (S.d. overall 1.5), odds ratio (OR) 0.35 per mmol/l (95% CI 0.17, 0.71)] and the association remained significant when adjusted for smoking [OR 0.33 per mmol/l (95% CI 0.16, 0.68)]. Current smokers had a reduced risk of GCA [OR 0.35 (95% CI 0.18, 0.70)]. Both cholesterol [mean 5.6 vs 6.0 mmol/l (S.d. overall 1.0)] and triglyceride levels [median 1.0 vs 1.2 mmol/l (S.d. overall 0.8)] were lower among the cases at baseline screening, with significant negative associations with subsequent GCA in crude and smoking-adjusted models [OR 0.62 per mmol/l (95% CI 0.43, 0.90) for cholesterol; 0.46 per mmol/l (95% CI 0.27, 0.81) for triglycerides].

Conclusion

Development of GCA was associated with lower FBG and lower cholesterol and triglyceride levels at baseline, all adjusted for current smoking, suggesting that metabolic features predispose to GCA.

Incidence and prevalence of giant cell arteritis in Ontario, Canada

OBJECTIVE

To estimate trends in the incidence and prevalence of GCA over time in Canada.

METHODS

We performed a population-based study of Ontario health administrative data using validated case definitions for GCA. Among Ontario residents ≥50 years of age we estimated the annual incidence and prevalence rates between 2000 and 2018. We performed sensitivity analyses using alternative validated case definitions to provide comparative estimates.

RESULTS

Between 2000 and 2018 there was a relatively stable incidence over time with 25 new cases per 100 000 people >50 years of age. Age-standardized incidence rates were significantly higher among females than males [31 cases (95% CI: 29, 34) vs 15 cases (95% CI: 13, 18) per 100 000 in 2000]. Trends in age-standardized incidence rates were stable among females but increased among males over time. Incidence rates were highest among those ≥70 years of age. Standardized prevalence rates increased from 125 (95% CI 121, 129) to 235 (95% CI 231, 239) cases per 100 000 from 2000 to 2018. The age-standardized rates among males rose from 76 (95% CI 72, 81) cases in 2000 to 156 (95% CI 151, 161) cases per 100 000 population in 2018. Between 2000 and 2018, the age-standardized rates among females similarly increased over time, from 167 (95% CI 161, 173) to 304 (95% CI 297, 310) cases per 100 000 population.

CONCLUSION

The incidence and prevalence of GCA in Ontario is similar to that reported in the USA and northern Europe and considerably higher than that reported for southern Europe and non-European populations.

Infections Are Associated With Increased Risk of Giant Cell Arteritis: A Population-based Case-control Study from Southern Sweden

OBJECTIVE

To investigate the association between infections and the subsequent development of giant cell arteritis (GCA) in a large population-based cohort from a defined geographic area in Sweden.

METHODS

Patients diagnosed with biopsy-confirmed GCA between 2000 and 2016 were identified through the database of the Department of Pathology in Skåne, the southernmost region of Sweden. For each GCA case, 10 controls matched for age, sex, and area of residence were randomly selected from the general population. Using the Skåne Healthcare Register, we identified all infection events prior to patients' date of GCA diagnosis and controls' index date. With infection as exposure, a conditional logistic regression model was employed to estimate the OR for developing GCA. The types of infections contracted nearest in time to the GCA diagnosis/index date were identified.

RESULTS

A total of 1005 patients with biopsy-confirmed GCA (71% female) and 10,050 controls were included in the analysis. Infections were more common among patients subsequently diagnosed with GCA compared to controls (51% vs 41%, OR 1.78, 95% CI 1.53-2.07). Acute upper respiratory tract infection (OR 1.77, 95% CI 1.47-2.14), influenza and pneumonia (OR 1.72, 95 % CI 1.35-2.19), and unspecified infections (OR 5.35, 95 % CI 3.46-8.28) were associated with GCA. Neither skin nor gastrointestinal infections showed a correlation.

CONCLUSION

Infections, especially those of the respiratory tract, were associated with subsequent development of biopsy-confirmed GCA. Our findings support the hypothesis that a range of infections may trigger GCA.

Malignancies in Giant Cell Arteritis: A Population-based Cohort Study

OBJECTIVE

To investigate the risk of cancer in patients with biopsy-proven giant cell arteritis (GCA) from a defined population in southern Sweden.

METHODS

The study cohort consisted of 830 patients (mean age at GCA diagnosis was 75.3 yrs, 74% women) diagnosed with biopsy-proven GCA between 1997 and 2010. Temporal artery biopsy results were retrieved from a regional database and reviewed to ascertain GCA diagnosis. The cohort was linked to the Swedish Cancer Registry. The patients were followed from GCA diagnosis until death or December 31, 2013. Incident malignancies registered after GCA diagnosis were studied. Based on data on the first malignancy in each organ system, age- and sex-standardized incidence ratios (SIR) with 95% CI were calculated compared to the background population.

RESULTS

One hundred seven patients (13%) were diagnosed with a total of 118 new malignancies after the onset of GCA. The overall risk for cancer after the GCA diagnosis was not increased (SIR 0.98, 95% CI 0.81-1.17). However, there was an increased risk for myeloid leukemia (2.31, 95% CI 1.06-4.39) and a reduced risk for breast cancer (0.33, 95% CI 0.12-0.72) and upper gastrointestinal tract cancer (0.16, 95% 0.004-0.91). Rates of other site-specific cancers were not different from expected.

CONCLUSION

In this Swedish population-based cohort of GCA, the overall risk for cancer was not increased compared to the background population. However, there was an increased risk for leukemia and a decreased risk for breast and upper gastrointestinal tract cancer.

Advantages in diagnosis of giant cell arteritis by ultrasound

Giant cell arteritis is the most common systemic vasculitis. It selectively affects large- and medium-sized arteries. Arterial wall inflammation leads to luminal occlusion and tissue ischemia, which cause the clinical manifestations of this vasculitis. Susceptible sites include the vascular bed of the cranial nerves and scalp including the temporal arteries, optic nerve, masseter muscles, and the posterior circulation of the central nervous system. Involvement can extend to the aorta and its primary and secondary branches, including the subclavian and axillary arteries, which leads to upper-extremity ischemia. The article presents a review of epidemiology, clinical presentation and especially ultrasound diagnostics of giant cell arteritis.

Giant cell arteritis in patients of Indian Subcontinental descent in the UK

BACKGROUND

GCA in the Indian Subcontinent (ISC) is rare. Our centre in London, UK, serves an ethnically diverse population, including a significant population of patients of ISC descent. We hypothesise that patients of ISC descent are no less likely than others to present with symptoms suggestive of GCA and therefore to undergo temporal artery biopsy (TAB).

METHOD

A retrospective audit of all TABs performed at our institution over an 8 year period, to identify ethnicity (white, black, ISC, other, unknown) and biopsy result. We compared the proportion of all patients of ISC descent attending the ED to the proportion of ISC patients undergoing TAB. We compared the proportion of positive TABs among ISC patients with positive TABs among white patients. We also compared the proportion of TAB in ISC patients with all non-ISC ethnicities combined.

RESULTS

The proportion of patients undergoing TAB who were of ISC descent (16.3% of 92) was comparable to the proportion of A&E attendances made up by ISC patients [p = 0.1339]. 3.8% (1/26) of positive biopsies were among patients of ISC descent. White patients were significantly more likely to have a positive biopsy than patients of ISC ethnicity (33% of 61 white patients vs. 7% of 15 ISC [p = 0.0456]), as were patients of non-ISC ethnicity (32.5% of 77 non-ISC patients vs. 7% of 15 ISC patients [p = 0.0464]).

DISCUSSION

At our centre, biopsy proven GCA occurs in patients of ISC descent, but rarely. Full investigation for GCA continues to be appropriate where it is suspected, regardless of ethnicity.

Large-vessel giant cell arteritis: diagnosis, monitoring and management

GCA is a chronic, idiopathic, granulomatous vasculitis of medium and large arteries. It comprises overlapping phenotypes including classic cranial arteritis and extra-cranial GCA, otherwise termed large-vessel GCA (LV-GCA). Vascular complications associated with LV-GCA may be due, in part, to delayed diagnosis, highlighting the importance of early identification and prompt initiation of effective therapy. Advancements in imaging techniques, including magnetic resonance angiography, CT angiography, PET and colour duplex ultrasonography, have led to improvements in the diagnosis of LV-GCA; however, the role imaging modalities play in the assessment of disease activity and long-term outcomes remains unclear. Glucocorticoids are the mainstay of therapy in LV-GCA, but their prolonged use is associated with multiple, sometimes serious, adverse effects. Recent data suggest that biologic therapies, such as tocilizumab, may be effective and safe steroid-sparing options for patients with GCA. However, data specifically evaluating the management of LV-GCA are limited.

The Role of Ultrasound Compared to Biopsy of Temporal Arteries in the Diagnosis and Treatment of Giant Cell Arteritis (TABUL): a diagnostic accuracy and cost-effectiveness study

BACKGROUND

Giant cell arteritis (GCA) is a relatively common form of primary systemic vasculitis, which, if left untreated, can lead to permanent sight loss. We compared ultrasound as an alternative diagnostic test with temporal artery biopsy, which may be negative in 9-61% of true cases.

OBJECTIVE

To compare the clinical effectiveness and cost-effectiveness of ultrasound with biopsy in diagnosing patients with suspected GCA.

DESIGN

Prospective multicentre cohort study.

SETTING

Secondary care.

PARTICIPANTS

A total of 381 patients referred with newly suspected GCA.

MAIN OUTCOME MEASURES

Sensitivity, specificity and cost-effectiveness of ultrasound compared with biopsy or ultrasound combined with biopsy for diagnosing GCA and interobserver reliability in interpreting scan or biopsy findings.

RESULTS

We developed and implemented an ultrasound training programme for diagnosing suspected GCA. We recruited 430 patients with suspected GCA. We analysed 381 patients who underwent both ultrasound and biopsy within 10 days of starting treatment for suspected GCA and who attended a follow-up assessment (median age 71.1 years; 72% female). The sensitivity of biopsy was 39% [95% confidence interval (CI) 33% to 46%], which was significantly lower than previously reported and inferior to ultrasound (54%, 95% CI 48% to 60%); the specificity of biopsy (100%, 95% CI 97% to 100%) was superior to ultrasound (81%, 95% CI 73% to 88%). If we scanned all suspected patients and performed biopsies only on negative cases, sensitivity increased to 65% and specificity was maintained at 81%, reducing the need for biopsies by 43%. Strategies combining clinical judgement (clinician's assessment at 2 weeks) with the tests showed sensitivity and specificity of 91% and 81%, respectively, for biopsy and 93% and 77%, respectively, for ultrasound; cost-effectiveness (incremental net monetary benefit) was £485 per patient in favour of ultrasound with both cost savings and a small health gain. Inter-rater analysis revealed moderate agreement among sonographers (intraclass correlation coefficient 0.61, 95% CI 0.48 to 0.75), similar to pathologists (0.62, 95% CI 0.49 to 0.76).

LIMITATIONS

There is no independent gold standard diagnosis for GCA. The reference diagnosis used to determine accuracy was based on classification criteria for GCA that include clinical features at presentation and biopsy results.

CONCLUSION

We have demonstrated the feasibility of providing training in ultrasound for the diagnosis of GCA. Our results indicate better sensitivity but poorer specificity of ultrasound compared with biopsy and suggest some scope for reducing the role of biopsy. The moderate interobserver agreement for both ultrasound and biopsy indicates scope for improving assessment and reporting of test results and challenges the assumption that a positive biopsy always represents GCA.

FUTURE WORK

Further research should address the issue of an independent reference diagnosis, standards for interpreting and reporting test results and the evaluation of ultrasound training, and should also explore the acceptability of these new diagnostic strategies in GCA.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Incidence of giant cell arteritis in Western Norway 1972-2012: a retrospective cohort study

Background

Giant cell arteritis (GCA) is the most common systemic vasculitis in persons older than 50 years. The highest incidence rates of the disease have been reported in Scandinavian countries. Our objective was to determine the epidemiology of GCA in an expected high-incidence region during a 41-year period.

Methods

This is a hospital-based, retrospective, cohort study. Patients diagnosed with GCA in Bergen health area during 1972–2012 were identified through computerized hospital records (n = 1341). Clinical information was extracted from patients’ medical journals, which were reviewed by a standardized method. We excluded patients if data were unavailable (n = 253), if the reviewing rheumatologist found GCA to be an implausible diagnosis (n = 207) or if the American College of Rheumatology (ACR) 1990 classification criteria for GCA were not fulfilled (n = 89). Descriptive methods were used to characterize the sample. Incidence was analyzed by graphical methods and Poisson regression.

Results

A total of 792 patients were included. The average annual cumulative incidence of GCA was 16.7 (95% CI 15.5-18.0) per 100,000 of the population ≥ 50 years old. The corresponding incidence for biopsy-verified GCA was 11.2 (95% CI 10.2–12.3). The annual cumulative incidence increased with time in the period 1972–1992 (relative risk (RR) 1.1, p < 0.001) but not in 1993–2012 (RR 1.0, p = 0.543). The incidence was higher in women compared to men (average annual incidence 37.7 (95% CI 35.8–39.6) vs. 14.3 (95% CI 13.2–15.5), p < 0.001) with women having a twofold to threefold higher incidence rate throughout the study period. Average annual incidence increased with age until the 7th decade of life in both sexes throughout the study period (2.8 (95% CI 2.3–3.3) for age <60, 15.5 (95% CI 14.4–16.8) for age 60–69, 34.5 (95% CI 32.8–36.4) for age 70–79 and 26.8 (95% CI 25.3-28.4) for age ≥80 years, p < 0.001 for all age adjustments).

Conclusions

Our study confirms an incidence of GCA comparable to previous reports on Scandinavian populations. Our results show increasing incidence from 1972 through 1992, after which the incidence has levelled out.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1479-6) contains supplementary material, which is available to authorized users.

Diagnosis, Management, and Outcome of Aortitis at a Single Center

BACKGROUND

Aortitis is a rare condition with inflammatory or infectious etiology that can be difficult to diagnose due to the highly variable clinical presentation and nonspecific symptoms. However, current literature on the diagnosis, management, and prognosis of aortitis is extremely scarce.

METHODS

We retrospectively reviewed all patients' charts who were diagnosed with giant cell arteritis, Takayasu arteritis, or noninfectious aortitis presenting at a single center between January 1, 2009, and April 17, 2015. Data collected included demographics, medical history, comorbidities, laboratory and imaging data, management, and outcome.

RESULTS

Among the included 15 patients presenting with aortitis at our center, 53% were diagnosed with Takayasu arteritis, 33% with idiopathic inflammatory aortitis, and 13% with giant cell arteritis. All patients received steroid treatment, 67% received adjunctive immunosuppressants or immunomodulators, and 33% underwent interventional procedures. Based on clinical presentation and laboratory and imaging findings at the last follow-up visit for each patient, 67% showed improvement, 27% had no change in disease activity, and 7% had a progression of the disease.

CONCLUSIONS

Takayasu arteritis was found to be more common than idiopathic inflammatory aortitis and giant cell arteritis among our 15 cases diagnosed with aortitis. All patients received medical therapy and 33% received interventional procedures, leading to 67% improvement of disease activity or related complications. This article also offers a comprehensive review of the diagnosis, management, and outcome of aortitis, supplementing the very limited literature on this disease.

Geo-epidemiology of temporal artery biopsy-positive giant cell arteritis in Australia and New Zealand: is there a seasonal influence?

Objective

Previous studies, although inconclusive, have suggested possible associations of environmental risk factors with the development of giant cell arteritis (GCA). We aim to investigate seasonal influence on the incidence of GCA across Australia and New Zealand.

Methods

In establishing an international study to investigate the molecular aetiology of GCA, archived temporal artery biopsy (TAB) specimens primarily from Australia and New Zealand were obtained. Demographic details including age, sex and date of TAB were collected from collaborating pathology departments. The season in which GCA was diagnosed was determined and compared with previous reports investigating the association between environmental risk factors and GCA.

Results

Our study comprises data from 2224 TAB-positive patients with GCA; 2099 of which were from patients in Australia and New Zealand. The mean age at time of diagnosis was 76.4 years of age. The female-to-male ratio was 2.2:1. We noted equal distribution of the incidence rate across all four seasons (530-580 cases diagnosed every quarter). Statistical analysis of seasonal variation by Poisson regression and cosinor methods showed no incidence preponderance across seasons. Our results do not support a seasonal component contributing to the onset of disease. Our literature search identifies no consistent environmental risk factor in association with GCA.

Conclusion

This is the largest GCA data set reported outside of Europe. Our results demonstrate equal distribution of the incidence rate across all four seasons. In contrast to some earlier reports, we did not identify evidence of a seasonal component contributing to the onset of disease.

Relative Frequencies of Arteritic and Nonarteritic Anterior Ischemic Optic Neuropathy in an Arab Population

BACKGROUND

To evaluate the relative frequencies of arteritic and nonarteritic anterior ischemic optic neuropathy (AION) in an Arab population and to compare and contrast these findings with known epidemiological data from Caucasian populations.

METHODS

A retrospective review of the medical records of all patients diagnosed with AION at the King Khaled Eye Specialist Hospital (KKESH) in Riyadh, Saudi Arabia, between 1997 and 2012.

RESULTS

Of 171 patients with AION, 4 had biopsy-proven giant-cell arteritis (GCA). The relative frequencies of arteritic anterior ischemic optic neuropathy (AAION) and nonarteritic anterior ischemic optic neuropathy (NAION) in this Arab cohort were 2.3% and 97.7%, respectively.

CONCLUSIONS

The relative frequencies of arteritic anterior ischemic optic neuropathy and nonarteritic anterior ischemic optic neuropathy differ between Arab and North American clinic-based populations, with giant-cell arteritis-related ischemia being much less frequent in Saudi Arabia.

The role of toll like receptors in giant cell arteritis

GCA is a common primary systemic vasculitis that results in granulomatous inflammation of medium to large arteries. Both innate and adaptive immune mechanisms combine to drive intimal hyperplasia, luminal stenosis and ultimately occlusion. While the pathogenesis of GCA is incompletely understood, the activation of resident adventitial dendritic cells via toll like receptors (TLRs) appears to be a crucial inciting event. Here we explore the role of TLRs in the pathogenesis of GCA, including their effects on dendritic cell and T cell activation and recruitment, putative infectious triggers for GCA and the potential of TLR inhibition as a novel therapeutic strategy in GCA.

New insights into the pathogenesis of giant cell arteritis and hopes for the clinic

Giant cell arteritis is a complex immune-mediated disease that involves large blood vessels in individuals older than 50 years. Recent studies have confirmed a strong association of this form of vasculitis with the HLA region, particularly with HLA class II genes. However, other non-HLA loci, such as protein tyrosine phosphatase non-receptor type 22, may also account for the susceptibility to giant cell arteritis. In addition, genetic variants located in genes encoding proinflammatory cytokines seem to influence the phenotypic expression of the disease, including the risk of severe ischemic complications, the presence of polymyalgia rheumatica and the higher incidence of relapses observed in some patients. The identification of putative genetic markers of disease severity could have clear therapeutic implications, as it may allow us to identify patients who are potentially responders to specific treatments.

Different Scoring Methods of FDG PET/CT in Giant Cell Arteritis: Need for Standardization

Giant cell arteritis (GCA) is the most frequent form of vasculitis in persons older than 50 years. Cranial and systemic large vessels can be involved. [¹⁸F] fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is increasingly used to diagnose inflammation of the large arteries in GCA. Unfortunately, no consensus exists on the preferred scoring method. In the present study, we aim to define the optimal FDG PET/CT scoring method for GCA diagnosis using temporal artery biopsy and clinical diagnosis as the reference method. FDG PET/CT scans of GCA patients (12 glucocorticoid-naive, 6 on glucocorticoid treatment) and 3 control groups (inflammatory, atherosclerotic, and normal controls) were evaluated. We compared 2 qualitative visual methods (i.e. (1a) first impression and (1b) vascular uptake versus liver uptake) and 4 semiquantitative methods ((2a) SUVmax aorta, (2b) SUVmax aorta-to-liver ratio, (2c) SUVmax aorta-to-superior-caval-vein ratio, and (2d) SUVmax aorta-to-inferior-caval-vein ratio). FDG uptake pattern (diffuse or focal) and presence of arterial calcifications were also scored. Diagnostic accuracy of the visual method vascular versus liver uptake (1b) was highest when the cut-off point "vascular uptake higher than liver uptake" (sensitivity 83%, specificity 91%) was used. Sensitivity increased to 92% when patients on glucocorticoids were excluded from the analysis. Regarding the semiquantitative methods, the aorta-to-liver ratio (2b) with a cutoff of 1.03 had the highest diagnostic accuracy, with a sensitivity and specificity of 69% and 92%, respectively. Sensitivity increased to 90% when patients on glucocorticoids were excluded. The number of vascular segments with diffuse FDG uptake pattern was significantly higher in GCA patients without glucocorticoid use compared with all control patient groups. CRP was not significantly different between positive and negative FDG PET scans in the GCA group. Visual vascular uptake higher than liver uptake resulted in the highest diagnostic accuracy for the detection of GCA, especially in combination with a diffuse FDG uptake pattern. Of the semiquantitative methods, the aorta-to-liver SUVmax ratio (cutoff point = 1.03) had the highest diagnostic accuracy. The diagnostic accuracy increased when patients using glucocorticoids were excluded from the analyses.

Do solar cycles influence giant cell arteritis and rheumatoid arthritis incidence?

OBJECTIVE

To examine the influence of solar cycle and geomagnetic effects on the incidence of giant cell arteritis (GCA) and rheumatoid arthritis (RA).

METHODS

We used data from patients with GCA (1950-2004) and RA (1955-2007) obtained from population-based cohorts. Yearly trends in age-adjusted and sex-adjusted incidence were correlated with the F10.7 index (solar radiation at 10.7 cm wavelength, a proxy for the solar extreme ultraviolet radiation) and AL index (a proxy for the westward auroral electrojet and a measure of geomagnetic activity). Fourier analysis was performed on AL, F10.7, and GCA and RA incidence rates.

RESULTS

The correlation of GCA incidence with AL is highly significant: GCA incidence peaks 0-1 year after the AL reaches its minimum (ie, auroral electrojet reaches a maximum). The correlation of RA incidence with AL is also highly significant. RA incidence rates are lowest 5-7 years after AL reaches maximum. AL, GCA and RA incidence power spectra are similar: they have a main peak (periodicity) at about 10 years and a minor peak at 4-5 years. However, the RA incidence power spectrum main peak is broader (8-11 years), which partly explains the lower correlation between RA onset and AL. The auroral electrojets may be linked to the decline of RA incidence more strongly than the onset of RA. The incidences of RA and GCA are aligned in geomagnetic latitude.

CONCLUSIONS

AL and the incidences of GCA and RA all have a major periodicity of about 10 years and a secondary periodicity at 4-5 years. Geomagnetic activity may explain the temporal and spatial variations, including east-west skewness in geographic coordinates, in GCA and RA incidence, although the mechanism is unknown. The link with solar, geospace and atmospheric parameters need to be investigated. These novel findings warrant examination in other populations and with other autoimmune diseases.

The incidence of giant cell arteritis in Olmsted County, Minnesota, over a 60-year period 1950-2009

OBJECTIVE

To assess the incidence of giant cell arteritis (GCA) in the era from 2000 to 2009.

METHOD

We extended the previously identified population-based cohort of Olmsted County, Minnesota residents who fulfilled 1990 American College of Rheumatology (ACR) criteria for GCA for earlier decades during 1950-1999.

RESULTS

In 2000-2009, 74 cases of GCA were identified (mean age 78.1 years; 80% women; 79% temporal artery biopsy positive; seven included based on radiological criteria). The incidence of GCA was 19.8 per 100,000 population.

CONCLUSIONS

The GCA incidence rates have remained steady since 1970 and the age at incidence, which was progressively increasing, seems to have reached a plateau.

Current concept and epidemiology of systemic vasculitides

Although a new classification algorithm for systemic vasculitides was proposed by Watts et al. and the Chapel Hill Consensus Conference (CHCC) was updated in 2012, there are currently no validated diagnostic criteria for systemic vasculitides. The Diagnostic and Classification Criteria for Vasculitis study (DCVAS) is a global study to develop and improve the diagnostic criteria for systemic vasculitides. The epidemiology of systemic vasculitides differs widely among countries. For example, in the case of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, patients with microscopic polyangiitis (MPA) and with positivity for MPO-ANCA are predominant in Asian countries, whereas patients with granulomatosis with polyangiitis (GPA) and with positivity for PR3-ANCA are predominant in northern Europe and the United States. Interstitial lung disease (ILD) occurs more frequently in Asian patients compared with patients in Europe. The incidence and the prevalence of large-vessel vasculitis also differ significantly. Giant cell arteritis (GCA) occurs frequently in northern Europe, unlike Takayasu arteritis (TAK). The ethnic and regional differences in the incidence, prevalence and clinical characteristics of patients with vasculitis should be recognized when we diagnose and treat patients with vasculitis using criteria, and should also be considered when interpreting the results from clinical studies.

Polymyalgia rheumatica: 125 years of progress?

OBJECTIVES

On the 125th anniversary of the first recognised publication on polymyalgia rheumatica, a review of the literature was undertaken to assess what progress has been made from the point of view of the clinical care of affected patients.

METHODS

The authors searched Medline and PubMed using the search terms 'polymyalgia rheumatica', 'giant cell arteritis' and 'temporal arteritis'. As much as possible, efforts were made to focus on studies where polymyalgia rheumatica and giant cell arteritis were treated as separate entities. The selection of articles was influenced by the authors' bias that polymyalgia rheumatica is a separate clinical condition from giant cell arteritis and that, as yet, the diagnosis is a clinical one. Apart from the elevation of circulating acute phase proteins, which has been recognised as a feature of polymyalgia rheumatica for over 60 years, the diagnosis receives no significant help from the laboratory or from diagnostic imaging.

RESULTS

This review has shown that, following the recognition of polymyalgia as a distinct clinical problem of the elderly, the results of a considerable amount of research efforts including those using the advances in clinical imaging technology over the past 60 years, have done little to change the ability of clinicians to define the disease more accurately. Since the introduction of corticosteroids in the 1950s, there has been also very little change in the clinical management of the condition.

CONCLUSIONS

Polymyalgia rheumatica remains a clinical enigma, and its relationship to giant cell arteritis is no clearer now than it has been for the past 125 years. Diagnosing this disease is still almost exclusively dependent on the clinical acumen of a patient's medical attendant. Until an objective method of identifying it clearly in the clinical setting is available, uncovering the aetiology is still unlikely, and until then, preventing the pain and stiffness of the disease while avoiding the problems of prolonged exoposure to corticosteroids is likely to remain elusive or serendipitous.

Aspirin as adjunctive treatment for giant cell arteritis

BACKGROUND

Giant cell arteritis (GCA) is a common inflammatory condition that affects medium and large-sized arteries and can cause sudden, permanent blindness. At present there is no alternative to early treatment with high-dose corticosteroids as the recommended standard management. Corticosteroid-induced side effects can develop and further disease-related ischaemic complications can still occur. Alternative and adjunctive therapies are sought. Aspirin has been shown to have effects on the immune-mediated inflammation in GCA, hence it may reduce damage caused in the arterial wall.

OBJECTIVES

To assess the safety and effectiveness of low-dose aspirin, as an adjunctive, in the treatment of giant cell arteritis (GCA).

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2013, Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to January 2014), EMBASE (January 1980 to January 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to January 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en) and the US Food and Drugs Administration (FDA) web site (www.fda.gov). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 24 January 2014.

SELECTION CRITERIA

We planned to include only randomised controlled trials (RCTs) comparing outcomes of GCA with and without concurrent adjunctive use of low-dose aspirin.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the search results for trials identified by the electronic searches. No trials met our inclusion criteria, therefore we undertook no assessment of risk of bias or meta-analysis.

MAIN RESULTS

We found no RCTs that met the inclusion criteria.

AUTHORS' CONCLUSIONS

There is currently no evidence from RCTs to determine the safety and efficacy of low-dose aspirin as an adjunctive treatment in GCA. Clinicians who are considering the use of low-dose aspirin as an adjunctive treatment in GCA must also recognise the established haemorraghic risks associated with aspirin, especially in the context of concurrent treatment with corticosteroids. There is a clear need for effectiveness trials to guide the management of this life-threatening condition.

Incidence and mortality rates of biopsy-proven giant cell arteritis in southern Sweden

OBJECTIVES

To study the epidemiology and mortality in patients with biopsy-proven giant cell arteritis (GCA) in southern Sweden.

METHODS

The study area was the County of Skåne. Patients with a positive temporal artery biopsy between 1997 and 2010 were identified using a regional register and a structured review of all histopathology reports. Standardised mortality ratios (SMR) were calculated using data for the Swedish population as the reference.

RESULTS

There were 840 patients with biopsy-proven GCA (626 women). The annual incidence rate per 100,000 inhabitants aged ≥50 years was 14.1 (95% CI 13.1 to 15.0); 7.7 (6.7 to 8.7) for men and 19.6 (18.1 to 21.1) for women, without seasonal variations. The incidence increased with age, with estimates of 2.0, 11.8, and 31.3 per 100,000 in the age groups 50-60, 61-70, 71-80 years, respectively (p<0.001). The age-standardised and sex-standardised incidence rate decreased from 15.9/100,000 in 1997-2001 to 13.3/100,000 in 2007-2010 (p=0.026). Two hundred and seventy-nine patients (207 women) died during the observation period. Mortality was significantly increased over the first 2 years after GCA diagnosis (SMR 1.52 (95% CI 1.20 to 1.85)), but not with longer follow-up. The estimated excess mortality was greater in women and in patients aged ≤70 years at diagnosis.

CONCLUSIONS

In this large population-based study of biopsy-proven GCA from southern Sweden, the incidence of GCA may have decreased over time. Short-term mortality was increased, in particular among those diagnosed at ≤70 years of age, but long-term survival was not impaired.

Induction of remission is difficult due to frequent relapse during tapering steroids in Korean patients with polymyalgia rheumatica

Polymyalgia rheumatica is an inflammatory disease affecting elderly and involving the shoulder and pelvic girdles. No epidemiological study of polymyalgia rheumatica was conducted in Korea. We retrospectively evaluated patients with polymyalgia rheumatica followed up at the rheumatology clinics of 10 tertiary hospitals. In total 51 patients, 36 patients (70.6%) were female. Age at disease onset was 67.4 yr. Twenty-three patients (45.1%) developed polymyalgia rheumatica in winter. Shoulder girdle ache was observed in 45 patients (90%) and elevated erythrocyte sedimentation rate (> 40 mm/h) in 49 patients (96.1%). Initial steroid dose was 23.3 mg/d prednisolone equivalent. Time to normal erythrocyte sedimentation rate was 4.1 months. Only 8 patients (15.7%) achieved remission. Among 41 patients followed up, 28 patients (68.3%) had flare at least once. Number of flares was 1.5 ± 1.6. The frequency of flare was significantly lower in patients with remission (P = 0.02). In Korea, polymyalgia rheumatica commonly develops during winter. Initial response to steroid is fairly good, but the prognosis is not benign because remission is rare with frequent relapse requiring long-term steroid treatment.

Giant cell arteritis: epidemiology, diagnosis, and management

Giant cell arteritis (GCA), also called temporal arteritis, is a vasculitis that affects large and middle-sized blood vessels--with predisposition to the involvement of cranial arteries derived from the carotid artery--in individuals older than 50 years of age. Familial aggregation of GCA has been observed. Incidence of GCA is higher in white individuals than those of other ethnicities, particularly those of Scandinavian background. A temporal artery biopsy is the gold standard test for the diagnosis of GCA. Several imaging modalities, in particular ultrasonography, are useful in the diagnosis of GCA. Corticosteroids are the cornerstone of treatment in GCA. Alternative, steroid-sparing drugs, particularly methotrexate, should be considered in GCA patients with severe corticosteroid-related side effects and/or in those who require prolonged corticosteroid therapy due to relapses of the disease.